[1] Radboud Univ Nijmegen, Med Ctr, Dept Primary & Community Care, NL-6500 HB Nijmegen, Netherlands
[2] McGill Univ, Ctr Hlth, Resp Epidemiol & Clin Res Unit, Montreal Chest Inst, Montreal, PQ, Canada
[3] Radboud Univ Nijmegen, Med Ctr, Dept Pulm Dis, NL-6500 HB Nijmegen, Netherlands
[4] Radboud Univ Nijmegen, Med Ctr, Dept Med Psychol, NL-6500 HB Nijmegen, Netherlands